| From 08640cf027d018f5361748973c7abe493fe20152 Mon Sep 17 00:00:00 2001 |
| From: Christian Borntraeger <borntraeger@de.ibm.com> |
| Date: Mon, 10 Feb 2020 11:27:37 -0500 |
| Subject: [PATCH] s390/uv: Fix handling of length extensions |
| |
| commit 27dc0700c3be7c681cea03c5230b93d02f623492 upstream. |
| |
| The query parameter block might contain additional information and can |
| be extended in the future. If the size of the block does not suffice we |
| get an error code of rc=0x100. The buffer will contain all information |
| up to the specified size and the hypervisor/guest simply do not need the |
| additional information as they do not know about the new data. That |
| means that we can (and must) accept rc=0x100 as success. |
| |
| Cc: stable@vger.kernel.org |
| Reviewed-by: Cornelia Huck <cohuck@redhat.com> |
| Fixes: 5abb9351dfd9 ("s390/uv: introduce guest side ultravisor code") |
| Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> |
| Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/arch/s390/boot/uv.c b/arch/s390/boot/uv.c |
| index ed007f4a6444..3f501159ee9f 100644 |
| --- a/arch/s390/boot/uv.c |
| +++ b/arch/s390/boot/uv.c |
| @@ -15,7 +15,8 @@ void uv_query_info(void) |
| if (!test_facility(158)) |
| return; |
| |
| - if (uv_call(0, (uint64_t)&uvcb)) |
| + /* rc==0x100 means that there is additional data we do not process */ |
| + if (uv_call(0, (uint64_t)&uvcb) && uvcb.header.rc != 0x100) |
| return; |
| |
| if (test_bit_inv(BIT_UVC_CMD_SET_SHARED_ACCESS, (unsigned long *)uvcb.inst_calls_list) && |
| -- |
| 2.7.4 |
| |
